Free books. Introduction to Operating System Concepts. What is an Operating System? Specialist Software for CS2S501

Transcription

1 Introduction to Operating System Concepts slide 1 Free books slide 2 Books Silberschatz, A. (2010). Operating System Concepts; 8th Edition, John Wiley &Sons. ISBN Ritchie C, Operating Systems: Incorporating UNIX &Windows 4th Edition, ISBN: Modern Operating Systems it.tdt.edu.vn/ tttin/giangday/hdh/ Modern Operating Systems.pdf The Minix Book tttin/giangday/hdh/operating Systems Design & Implementation 3rd Edition.pdf directed reading: read up to page 51 in Modern Operating Systems this week. Specialist Software for CS2S501 slide 3 What is an Operating System? slide 4 we will be using GNU/Linux $sudo apt-get install python gcc gdb make manpages-dev "A program that acts as an intermediary between a user of a computer and the computer hardware" Silbershatz, p1 probably other packages neccesary as well get a GNU/Linux account from: here mcgreg.comp.glam.ac.uk/login.html this url is only available on the campus network and not via the wireless network

2 What is an Operating System? slide 5 What is an Operating System? slide 6 "We can view an as a resource allocator. Acomputer system has many resources (hardware and software) that may be required to solve aproblem: CPU time, memory space, file storage space, I/O devices, and so on. user view vs. system view The acts as the manager of these resources and allocates them to specific programs and users as necessary for their tasks. Since there may be many, possibly conflicting requests for resources, the must decide which requests are allocated resources to operate the computer system efficiently and fairly." Silbershatz, p5 Operating system structure slide 7 Operating System kernel slide 8 user kernel - memory resident part of an which provides low level functions including interrupt handling, process scheduling, memory, file system support, I/O, communication,... user i/f os tools libraries applications system call interface kernel process memory input/output hardware control local hardware network

3 Mainframe Systems slide 9 slide 10 Memory Layout for a Simple System batching concept - similar jobs (programs) gathered together automatic job sequencing - automatically transfers control from one job to another first rudimentary user program area Memory Layout for Batch Systems slide 11 slide 12 Operating Systems features needed for multiprogramming job 1 Job 2 memory and disk CPU scheduling allocation of devices job 3 job 4

4 Time-Sharing Systems - Interactive Computing (Historical) slide 13 Operating Systems features needed for multiprogramming CPU is time multiplexed among several jobs that are kept in memory and on disk (CPU is allocated to a job only if the job is in memory) jobs are swapped in and out of memory to disk on-line communication between the user and the system is provided; when the finishes the execution of an operation, it seeks the next operation from the user Desktop System Revolution slide 14 personal computers - computer system dedicated to a single user user convenience and responsiveness - sole use of computer adaptation of technology developed for larger s different types of s (Windows, Mac OS X, Unix, GNU/Linux) - many variations of all these Computing Environments slide 15 Traditional Computing slide 16 traditional computing web-based computing mobile / ubiquitous computing many developments are products of older, traditional technologies mainframes / terminal access PC with/without network connections workstations, servers

5 Web/Internet - based computing slide 17 Mobile/Ubiquitous Computing slide 18 Characteristics Characteristics Advantages Advantages Disadvantages Disadvantages Operating Systems issues? Operating Systems issues? Further watching slide 19 Mainframes and the Unix Revolution